使用 python 检查重启后 AWS 实例是否启动

Question

有没有办法使用 boto3 或其他方式检查 AWS 实例是否最终出现在 python 中。运行状态不区分重新启动和最终启动阶段。

Answer 1

如果您只想检查远程端口是否打开，您可以使用内置的 socket 包。

这里是等待远程端口打开的 this answer 的快速修改：

import socket
import time

def wait_for_socket(host, port, retries, retry_delay=30):
    retry_count = 0
    while retry_count <= retries:
        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        result = sock.connect_ex((host, port))
        sock.close()
        if result == 0:
            print "Port is open"
            break
        else:
            print "Port is not open, retrying..."
            time.sleep(retry_delay)

Answer 2

boto3 文档中提供了所有信息 http://boto3.readthedocs.org/en/latest/reference/services/ec2.html

这将显示实例的所有信息。

import boto3
reservations = boto3.client("ec2").describe_instances()["Reservations"]
for reservation in reservations:
  for each in reservation["Instances"]:
    print " instance-id{} :  {}".format(each["InstanceId"], each["State"]["Name"])

# or use describe_instance_status, much simpler query
instances = boto3.client("ec2").describe_instance_status()
for each in instances["InstanceStatuses"]: 
  print " instance-id{} :  {}".format(each["InstanceId"], each["InstanceState"]["Name"])

来自文档：

State (dict) --

The current state of the instance.

Code (integer) --

The low byte represents the state. The high byte is an opaque internal value and should be ignored.

0 : pending
16 : running
32 : shutting-down
48 : terminated
64 : stopping
80 : stopped
Name (string) --

The current state of the instance.

事实上，文档里面并没有code state show "rebooting"。我无法在我自己的 EC2 实例上真正测试它，因为在我重新启动后，实例似乎重新启动得如此之快以至于 AWS 控制台没有机会显示 "Rebooting" 状态。

尽管如此，http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/monitoring-system-instance-status-check.html

The following are examples of problems that can cause instance status checks to fail:

Failed system status checks

Incorrect networking or startup configuration

Exhausted memory

Corrupted file system

Incompatible kernel

Answer 3

你也可以用InstanceStatusOk waiter in boto3 or whatever waiter是合适的。

import boto3

instance_id = '0-12345abcde'

client = boto3.client('ec2')
client.reboot_instances(InstanceIds=[instance_id])

waiter = client.get_waiter('instance_status_ok')
waiter.wait(InstanceIds=[instance_id])

print("The instance now has a status of 'ok'!")

使用 python 检查重启后 AWS 实例是否启动

To check whether AWS instance is up after reboot using python

python

python-3.x

amazon-web-services

boto3

aws-ec2